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This OEM transformer kit (part number 1173691) for the ICP/Heil/Tempstar model WJA336000K000B1 steps 208/230V line voltage down to the 24V control voltage that powers the thermostat, contactor coil, gas valve, and control board. Rated at 40VA, it supplies the low-voltage circuit for the entire system. The matching 24V barrier (part number 1176032) is included to insulate and protect the secondary terminals. When a transformer fails — usually from a shorted control circuit, lightning surge, or age — the system loses all 24V control power: the thermostat goes blank, the contactor will not pull in, and nothing energizes even though line voltage is present. A blown internal fuse or a burnt-out winding are the most common failure modes.
| Spec | Value |
|---|---|
| OEM Part Numbers | 1173691 (transformer), 1176032 (24V barrier) |
| Type | Step-Down Control Transformer |
| Brand | ICP / Heil / Tempstar |
| Rating | 40 VA |
| Primary Voltage | 208/230V |
| Secondary Voltage | 24V |
| Fitment | OEM Replacement |
Direct OEM replacement for ICP, Heil, and Tempstar model WJA336000K000B1, and shared across comparable Comfortmaker and Day & Night equipment using a 208/230V primary, 40VA control circuit. Confirm primary/secondary voltages and the 40VA rating against your existing transformer before installing.
Ships same day on orders placed before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.